\begin{{tabular}}{{ccccc}}
    \toprule
    \multirow{{4}}{{*}}{{\raisebox{{-\heavyrulewidth}}{{}}}}
        & \multicolumn{{2}}{{c}}{{\underline{{Using aggregated rig types}}}}
        & \multicolumn{{2}}{{c}}{{\underline{{Using disaggregated rig types}}}}
    \\
        & (a)
        & (b)
        & (c)
        & (d)
    \\
    \cmidrule{{1-5}}
        $1-R^2$
        & {r2_agg}
        & {r2_agg_2}
        & {r2_disagg}
        & {r2_disagg_2}
    \\
        $ SD(\tilde{{p}}_{{it}}) $
        & {p_tilde_agg}
        & {p_tilde_agg_2}
        & {p_tilde_disagg}
        & {p_tilde_disagg_2}
    \\
        $ SD(\hat{{p}}_{{it}}) $
        & {p_hat_agg}
        & {p_hat_agg_2}
        & {p_hat_disagg}
        & {p_hat_disagg_2}
    \\
        \cmidrule{{1-5}} Second order polynomial
        & No
        & Yes
        & No
        & Yes
    \\
    \bottomrule
\end{{tabular}}
